Pool Shock Power Blast (68% Cal Hypo) 24x1 Lb Bag - R20841-24



Model # R20841-24

  4.67 Average  



Model # R20841-24

Product Description

Cal-Shock 65  

Power Blast Cal Shock 65 is 68% Calcium Hypochlorite with 65% available chlorine. Our best selling shock treatment, Cal Shock 65 is in a fast dissolving granular form so it quickly destroys organic waste, algae and bacteria saving you time and money. 
  • 1 lb bags Calcium Hypochlorite
  • Powerful shock treatment great for spring start up
  • Gives quick chlorine boost
  • Ensure pool water is balanced for best results
  • Complete instructions for dosage on container
  • Compares To BioGuard Burn Out

For More Pool Chemicals

Product Specifications

# of 1 lb Bags:

?     Asked on 3/11/2017 by

I have a vinyl in-ground salt water swimming pool and last summer my chlorine levels would always drop quickly. I used tablets to keep the chlorine level in range for longer, is this ok? I was also told I should shock my pool every 2 weeks. Would you recommend this treatment and if so given the pool I have, which shock do you recommend and how often would you recommend I shock it?

A     Answered on 3/13/2017 by Scott W.

If you have your Cyanuric Acid between 40-50 ppm your salt system should have no problem keeping chlorine in the pool.

?     Asked on 3/14/2015 by Robert

Is this shock safe for my above ground pool?

A     Answered on 3/16/2015 by Robert M.

Hello Robert - This shock is safe for your above ground pool. We would recommend dissolving the shock in a bucket of water before it is poured into the pool.

?     Asked on 5/10/2013 by Guest

Will this shock increase my pH level? I need a shock that wont.

A     Answered on 5/10/2013 by Patrick P.

Any chlorine based shock will increase the pH. The only type of shock that will not, is a non-chlorine based shock: http://www.inyopools.com/Products/22300006058120.htm

?     Asked on 1/23/2013 by Guest

Do you carry swimming pool shock that is 100% calcium hypochlorite?

A     Answered on 1/23/2013 by Patrick P.

Unfortunately due to how unstable calcium hypochlorite is, there is no such thing. Our Zappit shock is one of the strongest on the market.

?     Asked on 12/20/2012 by Guest

I think I have a chlorine lock in my swimming pool. How did I get it and how can I get rid of it?

A     Answered on 12/20/2012 by Patrick P.

Chlorine lock is a condition in your swimming pool when the chlorine levels ( free chlorine and total chlorine) are not the same which makes the chlorine useless. You can read more here.

?     Asked on 12/20/2012 by Guest

What type of shock should I use in a bromine swimming pool?

A     Answered on 12/20/2012 by Patrick P.

If you are using bromine, you will want to use a non-chlorine shock. The non-chlorine shock will help sanitize the water through oxidation.

?     Asked on 12/20/2012 by Guest

Is there any way to prevent hair from turning green in the swimming pool.

A     Answered on 12/20/2012 by Patrick P.

The best way to prevent this is to treat for metals on a regular basis. Metal free can be used as part of your regular maintenance.

?     Asked on 12/20/2012 by Guest

I shocked my swimming pool and it turned green shortly afterward. What would cause that?

A     Answered on 12/20/2012 by Patrick P.

The change in color likely stemmed from the chlorine shock oxidizing the metals in your swimming pool. You can use this how to guide to get your swimming pool clear again.

?     Asked on 10/25/2012 by Guest

My swimming pool is clear but when my kids and I went swimming, our eyes burned. My neighbor came by and checked and said that the pool should be fine because he can smell the chlorine. What is wrong with my pool?

A     Answered on 10/25/2012 by Patrick P.

It sounds like you have chloramines. Chloramines are formed any time ammonia and nitrogen are in the water. Chloramines smell bad and cause skin and eye irritation. You can resolve the problem using this method.

?     Asked on 10/25/2012 by Guest

I keep the chemical levels (pH, alkalinity, calcium hardness, cyanuric acid and chlorine)in my pool within range but the water just doesn't seem right. Am I doing something wrong? Is there something I am missing?

A     Answered on 10/25/2012 by Patrick P.

I noticed you didn't mention your phosphates.  I would recommend checking the phosphate levels and using a phosphate remover as needed.

?     Asked on 10/25/2012 by Guest

Why do I need to shock the pool if I use chlorine tablets?

A     Answered on 10/25/2012 by Patrick P.

Chlorine tablets alone are not enough to keep the water sanitized. Pool shock helps to oxidize the water as well as breakdown chloramines.

?     Asked on 10/25/2012 by Guest

My pool company uses liquid shock in my pool. Is this granular shock any better?

A     Answered on 10/25/2012 by Patrick P.

Yes. If you look at the labels of both products, you will find that liquid shock is weaker. The bottle has vented caps (to vent chlorine gas) so the longer it sits on a shelf, the weaker it gets. Granular shock is a lot stronger and does not lose its strength as long as it's stored properly.

?     Asked on 10/19/2012 by Guest

No matter how much chlorine shock I put in my pool the chlorine level is always low. What can I do?

A     Answered on 10/19/2012 by Patrick P.

I would first make sure that you are testing the total chlorine AND free chlorine. If they are not the same reading, you may have a chlorine lock. If the chlorine levels are the same, I would check the pH, alkalinity and cyanuric acid levels.

?     Asked on 10/18/2012 by Guest

I have an in ground vinyl swimming pool and usually use liquid shock. I have heard that the granular shock is better but it's not for vinyl pools. Is there another type of shock that I can use that is stronger than the liquid?

A     Answered on 10/18/2012 by Patrick P.

You can use the granular shock but I would recommend adding it to a bucket of pool water to pre-dissolve it then pouring it along the perimeter of the pool.

?     Asked on 10/12/2012 by Guest

I tested my chlorine levels and they were at 0, so I shocked it. This didn't bring the levels up at all. What could be the problem and what should I do?

A     Answered on 10/12/2012 by Patrick P.

If your chlorine level remained at 0 after shocking, I would recommend checking the pH, alkalinity and cyanuric acid levels. I would also recommend checking the available chlorine percentage on the pool shock.

?     Asked on 1/25/2012 by Guest

I'm looking for pool shock to sanitize my drinking water. Will this work?

A     Answered on 1/25/2012 by Patrick P.

I have heard of people using pool shock to sanitize drinking water but I can not promote the use of any pool shock for this purpose. You will want to contact the NSF for further information.


Review Summary

  (Average 4.67 out of 5 stars)
15 Rating
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1 star:

The Most Helpful Review

1     0

 (5 out of 5 stars)  Works great at a great price

from fort lauderdale ()

Pros: Works well, dissolves fast, good price

Cons: None

This is a great low price for 68% Cal Hypo. It dissolved fast and works great. I sometimes skip shocking my pool because of the price of shock or because I've run out. After getting 2 boxes of this shock I'm sure my pool will be looking better than ever.

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The Most Recent Reviews

1     0

 (4 out of 5 stars)  works perfectly

from Greenville, SC ()

Pros: easy to use

I have used this for years and have never been happier. Works as advertised.

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 (5 out of 5 stars)  Pool shock


Product was shipped in a timely manner and works great.

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1     0

 (4 out of 5 stars)  Great pool shock

from Toms River, NJ ()

Am very please with how this product cleans my pool water

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 (3 out of 5 stars)  

from Vacaville, CA ()

FYI, when I received the order it was delivered in a crushed box. The contents were scattered all over and not very secure. Good pricing, good product, Very poor shipping Also, I did not receive the Cal-Shock 65 product which I used last year. I received "Zappit". I am hoping it will perform the same.

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 (4 out of 5 stars)  Good product but not that price competitive

from Houston, TX ()

Pros: Ease of ordering. Shipping is slightly more than sales tax locally.

Cons: Not price competitive for an on-line product.

Works as well as anything I've bought at retail but I've since found comparable products on sale locally for the same or less.

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 (5 out of 5 stars)  

from Valrico, FL ()

Polite CSR's, quick shipping and no ship charge on chemicals was a surprise. I would recommend you to anyone!Thanks!

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 (5 out of 5 stars)  Pool Shock 68% Cal Hypo 24x 1Lb Bag

from Arcadia, OH ()

Pros: convient one pound bags

Cons: some dusting

This is a fast acting high-strength shock that works in a minimal amount of time. Well worth the investment.

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